Selecting mechanism



E..P. BANCROFT.

SELECTING MECHANISM. APPLICAUON FILED JULY 19. 1917.

Patented Apr. 12, 1921.

q //7 ve /0n Erwin P 54/70/019.

Af/Sl.

ing description and claims,

ERWIN r. BANCROFT, or BROOKLYN, new YORK, ASSIGNOR T0 wEs'rERN nLEcTRIccomrAnY, INCORPORATED, on NEW YORK, N. Y., A CORPORATION OF NEW YORK,

sntno'rme MECHANISM.

nausea.

To all whom it may concern:

Be it known that I, ERWIN P. BA OROFT, a citizen of the United Statesresiding at Brooklyn in the county of Kings and State of New, 'Ybrk,have invented certain new and useful "Improvements in SelectingMechanisms, of which the following is a full, clear, concise, and exactdescription.

This invention relates to selecting mechanism particularly adapted foruse in high speed printing telegraph systems, although obviously notlimited to such use.

One of the principal objects of this invention is the provision of meanswhereby the operation of the selecting magnets is assured, even thoughthecurrent impulses, when distributed to the selecting magnets, are ofextremely short duration.

Another object 1s to provide suitable receiving mechanism of. theabovetype, re-

quiring a minimum of electro-mechanicalda VlCeS.

-A further object is tov provide an improved selecting mechanism capableof very rapid operation by allowing the selection of a character totakeplace simultaneously with the printing of the preceding characterselected.

To the above ends, a rotary current distributer is provided withconducting segments for distributing the effects of line currentimpulses to a plurality of selecting magnets. The selecting magnets arecontrolled by the line current impulses, and each magnet is providedwith a condenser connected in parallel therewith. In the systemdisclosed the selecting magnets are emloyed to select the desiredselectable; memhers and the actual work of moving theopcrating parts isperformed by a battery of cams carried by .a power driven shaft,-instead of employing an additional set of operating magnets for thispurpose. In addition to the receiving segments there is a local segmentcommon to each quadrant of the distributor, or to each'group ofreceiving segments-t Connected in a local circuit with each localsegment are operation-controlling magnets for" performing auxiliaryfunctions.

The above and other featuresofthis invention will be fully set forth inthe followand will be more reference to readily understood by in. whichFigure 1 companying drawings the acshows the circuit connections and theselecting magnets diagrammatically; and Fig. 2 1s a sectional view ofthe preferred form of selecting and printing mechanism of a telegraphreceiving printer.

The receiving current distributer 10 is of the usual well knownconstruction for multiple'x telegraphy and is provided with a' rotatablecurrent distributer arm 11 The distrlbuter head, as illustrated,consists of a receiving common ring 12, and a plurality of recelvlngsegments 15, 16, 17, 18, 19, etc., adapted to be connected with the ring12 by means of trailer brushes 35 and 36 carried 1' by the distributerarm 11. A local ring 13 1s also prov1ded and is likewise adapted toSpecification of Letters Patent. Patented Apr. 12, 19210 3 Applicationfiled m 19, 1917. Serial No. 181,557. Y i

be connected with alocal segment 14 during each quarter of a revolution.The receiving common ring 12 is connected to the tongue 20 of thelinerelay armature 21. The tongue 20 1s adapted to ply between contactpoints 22 and 23, which are connected to opposite termlnals of battery24, contact 22 being connected to the negative terminal and contact 23being connected to the positive termmal. Contact 22 is also connected toa condenser 25, and contact 23 is likewise connected with condensers 26and 27. As will be readily observed from the drawings, condensers 26 and27 are normally charged by battery 24 when the tongue 20 is out ofengagement with the contact 23, and the condenser 25 is normallychargediby battery 24 when the tongue 20 1s out of engagement withcontact 22, and ar adapted to be discharged under certain conditions as.will hereinafter appear.

The line relay 28 is connected in the line L and is shown provided withthe usual artiv ficial line AL for duplex working. Selecting magnets 30,31, 32, 33 and 34 are connected with the receiving segments 15; 16, 1.718 and 19 respectively. Connected in parallel with the selecting magnets30 to 34 inclusive, are condensers 40, '41, 42,

43 and 44 respectively, the purpose .of which W111 be ex lainedpresently. The local segment 14 '0 each quadrant is connected with Iother terminal of condenser 27 being connected. to the local ring 13. Itis obvious that the overlap and startingmagnets may be connected inparallel.

'In 2 is shown diagrammatically the essential details of the preferredform of selecting and printing mechanism. The selecting magnets to 34,inclusive, control the actuation of latches 50, 51, 52, 53 and 54respectively. The latches 50 to 54, inclu-, sive, normally extend underthe edges of seleeting bars '60," 61, 62, 63 and 64 respectively andthereby hold the selecting bars in their normal position. The selectingbars 60 'to 64 inclusive may be pivotally connected to the frame 45 inany suitable manner.

The springs 65 are constantly acting upon the selecting'bars 60 to 64inclusive, tending to draw them downward against their respective stops70, when released by their respective latches 50 to 54 inclusive. Apluspacing, automatic signaling, etc., as will a pear from a pendingapplication Serial 0. 173546 of Harry Pfannenstiehl. When one of theselectable code bars is per-' mitted to move forward it carries with ita pull bar 76 into the path of a reciprocating printing bar 77. Theactuation of the printing bar 77 iseffected by a cam 80 carried by arotatable shaft 78, which is normally under spring tension tending torotate. The cam shaft is adapted to be released for each revolutionbythe starting magnet 47. The printing bar 77 and selectable pull bar76, when forced down by the action of the cam 80, cause the desiredtype, carried by the type lever 83, to be thrust against the paperplaten 84, as will be readily understood by reference to Fig. 2.

. It is to be understood, of course, that a similar distributer may beused at the transmitting station and that some means must be providedfor maintaining synchronism between the two stations. Synchronism may bemaintained between the two distributers by means of a synchronizingsystem, such as disclosed in a copending application of Amos F. DixonSerial No; 869,784, wherein" the transmitters of adjacent quadrants arenormally connected to battery of opposite potential, thereby providingat least 111 current reversals durin each revolution of the distributerwhen t e transmitters are idle. However, any suitable synchronizingscheme may be employed with this system. In Fig. 1 a group of selectingmagnets is shown, connected to each of the four distributer quadrants,and arranged for four.

receivin channels. Obviously, by means of the dup ex line four channelsInayalso be worked in the opposite direction. In the embodimentdisclosed, the receiving segments of quadrants 1 and 3 are so connectedspond only to impulses of positive polarity,

.or to' the discharge of condenser 26, while the receiving segments ofquadrants 2 and 4 are connected so that the corresponding selectingmagnets respond only to impulses of negative polarity or to, thedischarge of condenser 25.

A better understanding of the selecting, and printing mechanism can beobtained from a .description 'of the selecting andprinting of a specificcharacter. Assume,- for example, that the letter B is to be selected andprinted, and that the combination of impulses required is positive,negative, negative, positive, positive. Also assume that the distributerarm 11 is in the position shown in the drawing, that is, the

.brush 35 is just starting upon the receiving segment 15. Then, as thefirst impulse is received over the linelL and through the line relay28,the armature 21 will be actuated to throw the contact tongue 20 intoengagement with contact 23. The instant the tongue 20 engages the lowercontact 23, the condenser 26,, which has previously been charged bybattery 24, will discharge through contact 23, tongue 20, common .ring a12, brush 36, distributer arm 11, brush 35, segment 15, selecting magnet30 and con denser 40 in parallel, and back to the other, side of thecondenser 26. Now, if the dis: tributer arm 11 is traveling at acomparatively slow rate of speed so that the segment 15 andreceivingring 12 are interconnected for a sufficient length of time tocause the actuation of selecting magnet 30, the condenser 40, connectedin parallel therewith, performs no useful function. However, if thedistributer arm is, traveling at a high rate of speed, which for highspeed operation may ';be assumed to be in the neighborhood of; 600revolutions per minute, the length of time that the brush 35 rests onsegment 15 will probably not'be suflicient to effect the actuation ofthe selectin magnet 30. The condenser 40 is used or the purpose ofprolonging the op erating pulse through the selecting magnet 30. Thiscondenser is charged whi-le the dis- 116 tributer brush is passing oversegment 15, and is permitted to discharge through magnet 30 the instantthe brush leaves segment 15, thereby prolonging the flow of currentthrough selecting magnet 30, and insuring 120 its operation. When theselecting magnet 30 is actuated it attracts its armature and withdrawsits respective latch 50 from engagement with its corresponding selecting'bar 60." The selecting bar is then permitted tact tongue 20 to bethrown against its upper contact 22. Now, when the contact tongue 20engages contact 22 and the distributer brushes interconnect segment 16and the receiving ring 12, the condenser 25 will not be dischargedthrough the second selecting magnet 31 because the circuit for magnet 31is connected back to the negative side of battery 24. Hence no currentwill flow. The same is true with respect to the third impulse, which isof negative polarity. lVith respect to the fourth impulse, however,which is of positive polarity, the line relay will cause the contacttongue 20 to move into engagement with the contact 23, and the condenser26 will discharge through the selecting magnet 33 and cause it tooperate as hereinbefore described in connection with selecting magnet30. When the selecting magnet 33 attracts itsarmature, causing itsrespective latch 53 to disengage its corresponding selecting bar 63, theselecting bar falls against its stop 70 and the latch 53 is locked inits actuated position by the holding pawl 58. \Vhen the brush 35 passesoff of segment 18, the charge in condenser 26 will again build up andthe instant the brush engages segment 19, the condenser 26 will againdischarge, but through the selecting magnet 34 and will effect itsoperation, as hereinbefore described in connection with'magnets 30 and33. The magnet 34 thereupon attracts its armature and withdraws itsrespective latch 54, thereby permitting selecting bar 64 to rest againstits stop 70, and the latch 54 is locked in its actuated position by theholding pawl 59. From Fig. 2 will be seen that the code bar 75 shown isnotched for the selection of the character B, and when the selectingbars 60, 63 and 64 move against their respective stops the selected codebar 75 will be drawn forward by the action of spring 65 The selectedcode bar in moving forward engages a pin 73 carried by its respectivepull bar 76. and moves-the pull bar into the path of the reciprocatingprinting'bar 77.

Immediately after the fifth line impulse is received the local segment14 is interconnected with the local ring 13 by means of brushes 37 and38 carried by the distributer arm l1. The instant the local ring 13 andsegment 14 are interconnected, the condenser 27, which is normallycharged, will discharge through the windings of the overlap magnet 46and starting magnet 47. The operation of. the starting magnet 47 startsthe printing mechanism in operation and the action of the overlap magnet46 places the selecting mechanism in readiness for a new selection. Thelatter will be described later. When the starting magnet 47 is energizedit attracts its armature and with draws the brake 79 from engagementwith a drum 85, thereby permitting the cam shaft the selecting andprintin 78 to rotate. -When the cam 80, carried by I platen 84, therebyeffecting the printing of the desired character. Any suitable means maybe provided for stopping rotation of the cam shaft at the end of eachrevolution, for example, the operation of the magnet 47 may be so timedas to permit the brake 79 to reengage the drum 85 and stop the rotationofv the cam shaft at the proper instant. The instant the desired typehas been thrust against the paper platen, the printing bar, pull bar,etc., may be restored to normal by suitable springs.

It is to be understood that the showing in Fig. 2 is purely diagrammaticand is for the purpose of illustratin one application of applicantsinvention. Tn actual practice mechanism disclosed in HarryPfannenstlehls pending application, Serial No. 173546 would be used.

The purpose of the overlap magnet .46 is to place the selectingmechanism in readiness for a new selection as soon as one selection hasbeen completed and simultaneously with the printing of the previouslyselected character.- The actuation of the overlap magnet causes the rack86 to move vertically, and release the pawls 55 to 59 inclusive from theactuated latches 50 to 54 inclusive. The operation of the overlap magnet.may be timed to take place as soon as the selecting bars are permittedto drop so'thatthe bentover portions of the selected latches, whenreleased, will abut against the actuated selecting bars. The purpose ofthe overlap magnet may be considered twofold. First, by releasing thelatches so that they abut against the selecting bars,v they are therebyaced in position tp move under the selectmg bars the instant the barsare restored to normal, or if the second character selected has positiveimpulses in common, or in the same order, with those of the precedinggroup of impulses, then some of the latches will be selected a secondtime in succession and will be withdrawn from against the selectingbars, before they are permitted to 1 move thereunder, thereby increasingsome- I what the selective action of the magnets which are required tofunction by successive groups of impulses.

The overlap and starting magnets are not provided with condensers inarallel therewith for the reason that the ocal segments may bemade ofsufficient length to insure the operation of the magnets withoutemploying condensers. for prolonging the 'fio'w of current therethrough,as in the case of the selecting magnets.

The purpose of the condensers 25 and 26 is to allow the use of highresistance in the cirv cuits of the selecting magnets and at the sametime permit the full potential of the battery 24 to be applied to theselecting magnets at the instant the circuits are closed. In this waythe apparatus is effectively protected against overheating either from acontinuous flow of current or from the application of higher voltages.

hat is claimed is:

1. Selecting mechanism comprising a current impulse distributer, aplurality, of selecting magnets connected thereto, a plurality ofcondensers of which at least one is normally charged, a relay forconnecting said condensers through said distributer to said selectingmagnets to effect their operation, and a condenser associated with eachselecting magnet for prolonging the fiow of current therethrough.

' 2. Selecting mechanism comprising a current impulse'distributer, anormally charged condenser controlled by said distributer, and aplurality of operation-controlling magnets adapted to be operated by thedischarge current from said; condenser.

3. Selecting mechanism, comprising a current distributer, selectingmagnets connected therewith, a line relay comprising a movable armatureassociated with said distributer, opposing contacts for said relayarmature, and

normally charged condensers connected with said contacts and adapted tobe discharged through the selecting magnets when said contacts areengaged by said armature.

4. Selecting mechanism, comprising a plurality of selecting magnets, acurrent impulse distr buter, a line relay cooperating with saiddistribute/r for determining the sequential operation of said magnets, acondenser, and a plurality of o'peration-controL ling magnets controlledby said distributer and said condenser independently of said relay.

5. Selecting mechanism, comprising a plurality of selecting magnetsdivided into rality of selecting magnets divided into groups, a linerelay comprising a movable armature, opposing contacts for said relayarmature, a pair of normally charged con- ,densers' connectedrespectively to said contacts and to alternate groups of said mag nets,and a current distributer coiiperating with the line relay for bringingthe selecting magnets under the influence of the discharged current ofthe said condensers.

In witness whereof I hereunto subscribe my name this 13th day of July,A. 1)., 1917.

ERl/VIN P. BANCROF T.

